I am running those covers on my smallblock. I had that problem also. The problem was the baffles that come with the valve covers has 3 holes for screws to attach it to the cover and for some strange reason there is an extra hole right where the oil filler hole is on the cover and the oil goes up through it into the breather and saturates it and then runs out onto the cover. I made another baffle without the extra hole and have not had this problem since. As for the PCV valve, it is a good idea to use one to help pull extra pressure from the engine. But you can also just use a breather cap on each cover and be fine, done this myself and seen many others like it. If you decide to do the PCV valve DO NOT cap the other cover, put a breather on it. I decided to do this on my car and made that mistake and oil went everywhere. Now I am going to have to pull the engine and put a new gasket set on it. I only made it about a mile down the road when the smoke started, opened the hood and oil was everywhere. After it happened I started asking myself why this happened then it hit me, all factory cars have the pcv valve but the other side had the vent going to the aircleaner and they have an oil cap. Still kicking myself for that screwup.
